Dental pin

Abstract

A dental pin used in building a superstructure on a tooth having a substantial portion thereof that has been removed. The pin comprises a shaft having a flute at the lower end thereof. The remainder of the shaft is threaded. The flute taps a hole that has previously been drilled in the tooth, and the threads on the shaft are retained in the tapped hole. Thus, the shaft is self-tapping. The shaft also includes an integral handle which permits the rotating of the pin into the tooth. A plurality of the pins are inserted in the tooth in a non-parallel relationship, and a superstructure is built on exposed portions of the pins. A fracture point is formed on each pin in order to break the head off after the pin has been inserted.

What is claimed as the invention is: 
     
       1. A dental pin comprising a shaft, a thread formed of said shaft, said thread having an arcuate outer edge, said shaft having a lower end, and means for tapping a thread in a tooth on said shaft, said tapping means comprising a cutting face on said thread, said cutting face being formed as the leading edge of said thread, said cutting face being formed at the lower end of said shaft, said shaft having a flute formed on the bottom thereof, said thread terminating at said flute, and said cutting face comprising the leading edge of said thread adjacent said flute. 
     
     
       2. A dental pin comprising a shaft .Iadd.having a flute formed at the lower end thereof .Iaddend.a thread formed on said shaft, .Iadd.said thread terminating at said flute, .Iaddend.said thread having an accuate outer edge, means .Iadd.on said shaft .Iaddend.for tapping a thread in a tooth .[.on said shaft.]., said tapping means comprising a cutting face on said thread, said cutting face being formed as the leading edge of said thread .Iadd.at the intersection of said flute with said thread.Iaddend., .[.said cutting face being formed at the lower end of said shaft,.]. and a handle on said shaft, said handle being integral with said shaft and positioned at the end of said shaft opposite said cutting face, said handle being circular in cross-section and having a diameter which is substantially larger than the diameter of said shaft .Iadd., whereby said handle facilitates the manual rotation of said pin when being inserted into a hole drilled in the tooth.Iaddend.. 
     
     
       3. A dental pin comprising a shaft .Iadd.having a flute formed at the lower end thereof.Iaddend., a thread formed on said shaft, .[.said shaft having a lower end,.]. .Iadd.said thread terminates at said flute, .Iaddend.means .Iadd.on said shaft .Iaddend.for tapping a thread on a tooth .[.on said shaft.]., said tapping means comprising a cutting face on said thread, said cutting face being formed as the leading edge of said thread .Iadd.at the intersection of said flute with said thread.Iaddend., .[.said cutting face being formed at the lower end of said shaft,.]. and a handle on said shaft, said handle being integral with said shaft, and positioned on the end of said shaft opposite said cutting face, said handle being circular in cross-section and having a diameter which is at least five times the diameter of said shaft .Iadd.whereby said handle facilitates the manual rotation of said pin when being inserted into a hole drilled in the tooth.Iaddend. . 
     
     
       4. The dental pin claim 3 wherein said handle is secured to said shaft by a pressed fit. 
     
     
       5. The dental pin of claim 3 wherein said handle has a roughened outer surface. 
     
     
       6. The dental pin of claim 5 wherein said roughened outer surface is provided by a plurality of grooves in said handle. 
     
     
       7. The dental pin of claim 3 and further including a fracture groove of reduced thickness formed on said shaft, said fracture groove being formed between said cutting face and said handle.  .[.8. A method of securing a dental pin of a specific diameter in a tooth comprising drilling at least one channel from a tooth surface into the tooth dentin, the diameter of said channel being smaller than the diameter of the dental pin, said dental pin being threaded, with the thread having an arcuate outer edge, and said dental pin having a self-tapping cutting face on the leading edge of said thread, and progressively introducing said dental pin into said channel by rotating the same so as to cut a helical thread on the interior wall of said channel by the self-tapping action of said dental pin, and whereby the arcuate thread fills said cut thread in order to obtain maximum holding force on the dental pin, while the same time residual stresses are minimized by the cut helical thread..]. .[.9. The method of claim 8 wherein a plurality of said channels are drilled in said tooth and one of said dental pins is inserted in each of said channels, and further including the step of building a superstructure on the tooth about portions of said dental pins which project above the tooth surface..]. .[.10. The method of claim 9 wherein said dental pins are inserted into said tooth in a non-parallel relationship..]..Iadd. 11. A dental pin comprising a shaft having a flute formed at the lower end thereof, a thread formed on said shaft, said thread terminating at said flute, means on said shaft for tapping a thread in a tooth, said tapping means comprising a cutting face on said thread, said cutting face being formed as the leading edge of said thread at the intersection of said flute with said thread, and a handle on said shaft, said handle being integral with said shaft and positioned to the end of said shaft opposite said cutting face, said handle having a dimension transverse to the axis of said shaft which is substantially larger than the diameter of said shaft, whereby said handle facilitates the manual rotation of said pin when being inserted into a hole drilled in the tooth. .Iaddend..Iadd. 12. The dental pin of claim 11 wherein said shaft has a fracture groove of reduced thickness between said cutting face and said handle. .Iaddend..Iadd. 13. A dental pin comprising a shaft having a flute formed at the lower end thereof, a thread formed on said shaft, said thread terminating at said flute, means on said shaft for tapping a thread in a tooth, said tapping means comprising a cutting face on said thread, said cutting face beng formed as the leading edge of said thread at the intersection of said flute with said thread, and a handle on said shaft, said handle being integral with said shaft and positioned on the end of said shaft opposite said cutting face, said handle having a dimension transverse to the axis of said shaft which is at least five times the diameter of said shaft, whereby said handle facilitates the manual rotation of said pin when being inserted into a hole drilled in the tooth. .Iaddend..Iadd. 14. The dental pin of claim 13 wherein said shaft has a fracture groove of reduced thickness between said cutting face and said handle. .Iaddend.